Presbyopia is usually treated with multifocal eyeglasses, progressive eyeglasses or contact lenses. Many methods for creating and manufacturing of progressive lenses are known in the art, such as polishing a semi-finished lens or molding. LASIK and other types of surgery cannot prevent or remedy this natural occurrence, which gradually affects nearly everyone over age 40. The visual effects caused by Presbyopia may slowly worsen for several years, requiring new changes in lens prescription, but will stabilize by age 65 or 70.
Corrective lenses are used in eyeglasses to correct Presbyopia and other disorders of accommodation. A basic solution for Presbyopia is the use of multifocal spectacle lenses. Multifocal spectacle lenses contain two or more lens powers to help you see objects at all distances. Bifocals contain two lens powers; trifocals contain three.
Progressive spectacle lenses are characterized by a gradient of increasing lens power, added to the wearer's correction for the other refractive errors. The gradient starts at the wearer's distance prescription, at the top of the lens and reaches a maximum addition power, or the full reading addition, at the bottom of the lens. The addition in middle of the lens usually enables reading text on a computer screen. The length of the progressive power gradient on the lens surface depends on the design of the lens, with a final addition power between 0.75 and 3.50 diopters. The addition value prescribed depends on the level of presbyopia of the patient.
The main disadvantages of multifocal eyeglasses and progressive lenses are their high cost and their need for professional adaptation.
There is thus required a method and system that provides a reasonable solution for the Presbyopia problem, while keeping a very low price that enables use of progressive lenses by everyone who needs it. Such a solution usually will not require a professional adaptation.